In the current life: academic, economist, bon vivant—eclectically so.
In the next life: Highlord of The Vampire Empire—future Transylvania.
In the current life: academic, economist, bon vivant—eclectically so.
In the next life: Highlord of The Vampire Empire—future Transylvania.
From mid May to mid July 2016 I shall be visiting again NIPE at EEG, Universidade do Minho, in Braga, Portugal. I have enjoyed their hospitality through several previous short term visits in recent years.
Since 11/2014, I am Associated Researcher at the Swedish Institute for Social Research, Stockholm University. I also have current affiliatiations with the research centers CCP (Denmark), CELSI (Slovakia), and NIPE (Portugal).
Between 01/2015 and 04/2015, I was Visiting Professor at the Einaudi Institute for Economics and Finance in Rome. From 05/2013 to 10/2014, I was Visiting Faculty at the Department of Economics, Stockholm University. In the interval 05/2010-05/2013, I was Marie Curie Individual International Outgoing Fellow (IOF), under EU Commission’s FP7-People Marie Curie Actions Program, at the Department of Economics, Northwestern University (“outgoing host”; first 2 of 3 years), and the Department of Economics and Business, Aarhus University (“EU host”; 3rd year). I am privileged and honored to have had Dale Mortensen as scientific mentor for that Marie Curie IOF project, and beyond.
Microeconometrics, Labor Economics, Empirical Industrial Organization, Real Options, Social Networks, Personnel Economics
* I maintain a more detailed page on my research in Economics, which includes titles and abstracts of other research in progress.
Peer-reviewed journal publications:
Unpublished research available in working paper format:
Published dissertations and scientific reports:
Publications and dissertations in other fields than Economics:
I am primarily a Labor Economist and Microeconometrician, with further, eclectic, interests in theoretical or empirical modeling tools more typical of Finance, Game Theory, Industrial Organization, and Social Networks. Thematically, most of my research to date studies labor market-type phenomena revolving around, e.g., human capital accumulation and dynamics of worker careers; bargaining, rent-sharing, and wage formation; persistent wage and employment inequality; incentive pay schemes; firm performance, investment in (in)tangibles, and employee outcomes. Methodologically, my research expertise is particularly developed in relation to: noncooperative game theory, real option theory, and search & matching theory—especially applied in labor market contexts; theoretical and applied dimensions of cross-sectional and panel-data econometrics.
Returns to Tenure or Seniority? (with Miguel Portela, Coen Teulings and Aico van Vuuren), March 2014, Econometrica, 82 (2), pages 705–730, DOI: 10.3982/ECTA8688 . See also the corresponding Web Appendix or the old July 2009 version (includes theory framework)
This study documents two empirical facts using matched employer-employee data for Denmark and Portugal. First, workers who are hired last, are the first to leave the firm. Second, workers’ wages rise with seniority, where seniority is defined as a worker’s tenure relative to the tenure of his colleagues. Controlling for tenure, the probability of a worker leaving the firm decreases with seniority. The increase in expected seniority with tenure explains a large part of the negative duration dependence of the separation hazard. Conditional on ten years of tenure, the wage differential between the 10th and the 90th percentile of the seniority distribution raises is 1.1-1.4 percentage points in Denmark and 2.3-3.4 in Portugal.
Keywords: wage dynamics, tenure, seniority, Last-In-First-Out
JEL-codes: J31, J41, J63
Tenure Profiles and Efficient Separation in a Stochastic Productivity Model (with Coen Teulings), May 2014, Journal of Business and Economic Statistics, 32:2, pages 245-258, DOI:10.1080/07350015.2013.866568 . See also the corresponding Web Appendix or the accepted, non-gated, November 2013 version. NB. This paper had a 2nd R&R at the Review of Economic Studies earlier.
We develop a theoretical model based on efficient bargaining, where both log outside productivity and log productivity in the current job follow a random walk. This setting allows the application of real option theory. We derive the efficient worker-firm separation rule. We show that wage data from completed job spells are uninformative about the true tenure profile. The model is estimated on the PSID. It fits the observed distribution of job tenures well. Selection of favourable random walks can account for the concavity in tenure profiles. About 80% of the estimated wage returns to tenure is due to selectivity in the realized outside productivities.
Keywords: random productivity growth, efficient bargaining, job tenure, inverse gaussian, wage-tenure profiles, option theory
JEL-codes: C33, C41, J31, J63
How Productive is Workplace Health and Safety? (with Elena Cottini and Niels Westergaard-Nielsen), forthcoming at the Scandinavian Journal of Economics (accepted in December 2015), DOI:10.1111/sjoe.12184. See also the corresponding Online Appendix.
This paper investigates the causal impact of workplace health and safety practices on firm performance, using Danish longitudinal matched employer-employee data merged with unique cross-sectional representative firm survey data on work environment conditions. We estimate standard production functions, augmented with workplace environment indicators, addressing both time-invariant and time-varying potentially relevant unobservables in the production process. We find positive and large productivity effects of improved physical dimensions of the health and safety environment (specifically, “internal climate” and “repetitive and strenuous work”).
Keywords: occupational health and safety, work environment, firm performance, production function estimation
JEL codes: C33, C36, D24, J28, L23
Downloadable working papers
A Social Network Analysis of Occupational Segregation (with Marco van der Leij), latest version Oct 2014; current stage: in revision
We develop a network model of occupational segregation between social groups divided along gender or racial dimensions, generated by the existence of positive assortative matching among individuals from the same group. If referrals are important for job search, then expected homophily in the structure of job contact networks induces different career choices for individuals from different social groups. This further translates into stable occupational segregation equilibria in the labor market. We derive conditions for wage and unemployment inequality in the segregation equilibria and characterize both 1st and 2nd best social welfare optima. Surprisingly, we find that utilitarian socially optimal policies always involve segregation, but that additional distributional concerns can justify integration policies.
Keywords: Social Networks, Homophily, Occupational Segregation, Labor Market Inequality, Social Welfare
JEL codes: J24, J31, J70, Z13
Firm downsizing, public policy, and the age structure of employment adjustments (with Hans-Martin von Gaudecker), latest version Oct 2015; current stage: in revision.
This paper studies the structure of workforce adjustments when firms facing adverse demand conditions are offered public financial incentives for downsizing. In particular, we are interested in how the age composition of employee outflows is shaped by corresponding age-dependent institutional arrangements. Our simple labour demand framework, with stochastic product demand and firing costs heterogenous in workers’ early retirement eligibility, has as core prediction that distressed firms will dismiss with predilection those employees eligible to retire early. We test the model’s implications on the entire set of mass layoff events in larger Danish private firms over 1980-2001, period covering several reforms to the early pension system. Our empirical conclusion is that that firms behave as predicted by our model with regards to their lower-educated workforce, but not towards their higher-educated employees. We conjecture that an extension of our baseline firm-level model to narrow within-firm employee categories with potentially asymmetric turnover responses to firm-level demand shocks can rationalize this finding.
Keywords: early retirement, labour demand, employment adjustment, mass layoffs, LEED
JEL-codes: H32, H55, J26, J65
Work in Progress (plus some temporarily abandoned projects)
We provide a fresh analysis of the theory of compensating wage differentials (CWD) using rich data on self-reported work environment conditions and worker risk attitudes, from a representative 5-wave (1990-2010, 5-year spaced) panel survey of workers, which we link to the Danish register, longitudinal, yearly, matched employer-employee data. Our study improves and extends previous CWD empirical analysis in several ways: a) in standard hedonic wage equations, we control for both individual and firm-specific time-invariant unobserved heterogeneity; we also report spell-first-difference estimates where workers report changes in work conditions within the same job spell; b) we account for worker heterogeneity in attitudes towards health/ safety risks, from information on workers’ smoking habits and on their being parents of young children; c) we compare results in a) and b) with alternative results obtained by estimating the workers marginal willingness to pay for job amenities from their job separation hazards. For a), we find that the only work environment conditions compensated for by hourly wage premia, in the order of 4-6%, are related to flexibility in the working time (“shift premia”), namely “working in irregular shifts”, “working in the evening” and “working at night”. If we account for the selection of workers in hazardous jobs based on the observed worker risk proxies and time-invariant worker unobservables, we find negative selection of risk-lovers into shift-jobs, with sizable hourly wage premia of 18-26%, while positive or no selection, and no compensation, in other types of hazard work. Finally, shift-jobs CWD estimates based on the worker’s employment history have magnitudes in between those at a) and b). We rationalize our results via a parsimonious model of job hazard premia and worker risk profiles.
We investigate the effects of performance pay (PP) on individual wage growth, within and between-firm earnings inequality, and worker-firm separation, using exhaustive Portuguese linked employer-employee longitudinal data for 1986-2007. This is the first economy-wide study in the incentive compensation literature attempting to account for the endogenous compensation policy of firms and for endogenous selection of workers across PP and non-PP firms. In our empirical analysis we are able to control for both unobserved worker and unobserved firm specific heterogeneity, and to proxy for the firm’s costs of switching across PP and non-PP regimes. Inter alia, emphasis is placed on the determinants, effects, and dynamics of managerial incentive pay and turnover. We rationalize our findings by means of an extended Lemieux, MacLeod and Parent (2009, QJE) model.
We provide microfoundations for worker seniority (a worker’s tenure relative to the tenure of all her co-workers at the firm) as natural bargaining device in large firms with stochastic product demand and irreversible firm-specific investments required for each newly hired worker. The firm and its workers simultaneously bargain for layoff order and wage schedule, whereupon infra-marginal senior workers get wage premia and layoff insurance. Buhai et al (2014, ECTA) have already shown empirically that wages increase and job exit hazard decreases with seniority, on exhaustive linked-employer-employee-data from Denmark and Portugal. Using the same data, and econometric methodology adapted from both Buhai and Teulings (2014, JBES) and Buhai et al (2014, ECTA), we argue that the seniority profile in wages is a proxy for the return to the extent of worker-firm specific investments.
Published Dissertations & Scientific Reports
Essays on Labour Markets: Worker-Firm Dynamics, Occupational Segregation and Workplace Conditions (digital version accessible via the EUR online repository), PhD Thesis 2008, Erasmus University Rotterdam/ Tinbergen Institute, published as book by Thela Thesis -Academic Publishing Services, in the Tinbergen Institute Research Series (no. 431), Amsterdam, The Netherlands; November 2008
Wages, Seniority and Separation Rates in a Stochastic Productivity Model: A Comparative Perspective, MPhil Thesis 2003, Tinbergen Institute, published as monograph by the Lumen Publishing House (Editura Lumen), Iasi, Romania; February 2006
Quantile Regression: Overview and Selected Applications, Ad-Astra Journal (Young Romanian Scientists’ Journal), Vol. 4, 2005
Selected unpublished work from my graduate student days (surveys, reports, course papers, etc.)
* For research publications in other fields than Economics see my CV page; you can check out also the list of courses followed during my graduate programs at the Tinbergen Institute, with (non-updated) links to their instructors’ webpages (for external summer schools and workshops, see corresponding section in my extended CV).
Next to the selected essays from below, I also post regularly on the followings weblogs:
Most essays collected here target a wider audience, i.e., not only academic, or at least not only academic Economists, though often scientific research and/or other academe-originating methods/ concepts are to some extent involved. The documents linked below are for the most part in Romanian, but with brief explanations around them in English. Related relevant material is available under various news media formats on my media-coverage page. You can also find a selection of my undergrad student essays (all in English) from University College Utrecht, Utrecht University, on my “UCU” page.
Click on the icon to download PDF copies of these articles or follow the weblinks to online versions. Neither the brief explanations nor the links are typically updated subsequent to their initial posting, hence it is possible, e.g., that some links have ceased working (I have sometimes anticipated that by also providing print-screen PDFs of the initial document versions).
Selection of some relatively recent essays/ presentations:
Selection of older essays and presentations, published in various Romanian mass-media (online and/or in print format):
First some short articles (in unedited version) published within the Educational Supplement of the newspaper Gandul, on the lives of several Nobel Laureates (that section is actually called, in direct translation from Romanian, “the Nobel Laureates are also humans…”). I don’t know yet if I will continue with this series.
I also published a short economic article (the most difficult part was to keep it that short) in the newspaper Cotidianul.
I wrote another article
initially for the same newspaper Cotidianul but apparently they did not like it (I say “apparently”, since in fact I was never given a reason for “why not”, which is what I would have expected from rational people) so at the very end of the day I ended up just posting it on my blog. Well, who’s interested will find it, read it and- you’re welcome to, by the way- comment on it and on anything else that you find on this page.
I continue with the listing some articles that were initially published on the Romanian online independent portal “Romania, Libera in Viitor” (RLIV), within its weekly electronic publication called “ACUM” (you can find all other articles I wrote for RLIV-ACUM here), sometimes followed by their commenting or re-publication also in other mass-media outlets.
Highlights from RLIV-ACUM (especially articles concerned with science and research policy in Romania):
My questions concerning the status of scientific research in Romania from the second part of this article (the essay was published here, in the RLIV-ACUM’s “Research, Science, Technology” (in Romanian: “Cercetare, Stiinta, Tehnologie”) section that I founded and maintained as editor until June 2005), inspired from the questions addressed by the prestigious journal Science to the USA presidential candidates and addressed to the Romanian presidential candidates in 2004, were publicly sustained by means of open letters, by the Ad-Astra Association of Romanian Researchers (in Romanian: Asociatia “Ad-Astra” a Cercetatorilor Romani), the Romanian Academic Forum (in Romanian: Forumul Academic Roman=FAR) and by several scientists of Romanian origin, including the Nobel Prize Laureate, Professor George Emil Palade. Some accounts in the mass-media and on the web sites of the organizations involved can be read in what follows: press communicate FAR, press communicates Ad-Astra, open letter signed also by Prof. Palade, other echoes in the Romanian mass-media: Evenimentul Zilei (also here and here), Ziua (also here), Romanian Global News (also here). Two of the Romanian presidential candidates answered the questions, Mr. Marko Bela and Mr. Adrian Nastase. A reaction of FAR to these two answers can be read here.
This short essay is the result of a joint brainstorming of several Romanian scientists working in research outside Romania, voluntarily organized in a taskforce to help the Romanian Ministry of Education in its planned reform of the Romanian High Education and Research sectors- it summarizes imperative measures needed to reform the doctoral programs in Romania and to consequently contribute to the rebirth of the Romanian doctoral prestige. It was published here, in the section “Cercetare, Stiinta, Tehnologie” of RLIV-ACUM. Miruna Munteanu wrote an excellent article related to this document in Ziua.
I wrote this essay linked above for the conference “Migration of Young Romanian Researchers: Performances and Possibilities of Return”, organized by the Romanian Cultural Institute (Institutul Cultural Roman=ICR) in Sinaia,October 2004. The essay can be found on the site of the ICR, it was published also on RLIV-ACUM (here with the abstract in the beginning as well), and in the Ad-Astra Journal.
Some people in the audience totally disagreed with me, but that presentation seemed to be interesting (provoking?) enough to get me quite a few subsequent interviews for Romanian TV channels, radio, and press…
Other— random selection—articles published in RLIV-ACUM (selection):
Below you can check out a selection of press/ magazine articles & other news media, including, e.g., television talk-shows, where I have been interviewed/ quoted/ invited (with saved PDF versions — by clicking on below — where possible, should the direct links not work any longer); note that the vast majority of these news media items below are in Romanian, though they have some explanations in English (if at all; started doing that only for newer items). The starred ones are larger contributions (such as, for instance, long interviews or talk-shows). In reverse chronological order:
See also a bunch of random links from my older website, which I will (re)organize as soon as possible…